BoilerFaultCodesYour boiler is currently set to a specific maintenance mode used by engineers to replace internal parts, rather than being in a fault state.
This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.
Technical description: To move the diverter valve to mid-position for replacement
What causes this fault?
This code appears because the boiler has been manually put into a specialized service mode by a person pressing specific buttons on the control panel. It is not caused by a mechanical failure, but rather by the system being told to move the internal diverter valve to a central position so it can be safely swapped or repaired. The boiler will remain in this state and will not provide heating or hot water until the mode is exited.
DIY fix possible
Switch the mains power to the boiler off and then back on againAlternatively, turn the mode knob away from the reset positionWait for the boiler to complete its start-up sequence to return to normal operation
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